I just finished building a countertop for an island at a house I am renovating. I found that Lowes and Depot both carry slab pine, which are pieces of pine glued together to form a slab 3/4 in thick and one inch thick. They come in 24 wide by 48 and 60 inch lengths. I fiddled around with it and added some depth and width and thickness (I needed 1.5 inches thick) and it came out pretty nice. Also, I screwed it to a piece of 3/4 in plywood to give it sturdiness (no warping or twisting) and weight, then put like trim pieces to give it that “cutting board” look. Everyone who has seen it has commented on how they wish they had something like it for their house as a work station.
I put a laquer base finish on it and polished it between coats with 220 paper and 00 steel wool.
I hope this helps, good luck!